In today's age, machines have completely changed lives, ranging from the first computer to cellphones. However, the most precise and well-articulated systems remain those that nature has built. The human body is an example of one such system which remains to be re-engineered.
Organ transplantation has existed since the mid-1800s when the first skin transplant was performed. Since this time, transplantation has exploded, resulting in the transplantation of an organ or limb or even several organs/limbs simultaneously. Initially, organs only from living identical twins were transplanted. However, soon thereafter organs were transplanted from the living and deceased, providing that the patient and donor have close genetic similarities. The donors could be a family member or even a genetically compatible stranger. In fact, more than 600,000 transplants have occurred in the United States since 1988.
The quest for donor tissues and organs is a slow and uphill battle. Simply stated, there are not enough donor tissues and organs and more than 6,000 people die each year due to organ failure. There are presently over 120,000 people in the US alone on waiting lists for organs and others experiencing chronic problems due to the long-term damaging effects of post-transplant immunosuppression. This has prompted significant research and tests on fabricating mechanical organs and transplanting tissue and organs from non-humans, neither of which has had much success. Unfortunately, the need for donor tissues and organs has also resulted in the black-market sale of tissues and organs from both willing and unwilling individuals.
Donor tissues, organs, and even animals are also used in the testing and evaluation of pharmaceutical drugs. In fact, in bringing a pharmaceutical drug to the market, it takes years, even decades of animal testing before clinical trials on humans may be performed. Not only do some have the view that animal testing is inhumane, but it is expensive and inefficient, particularly in situations where the pharmaceutical drug fails to make it to market.
Animal tissues and organs are incredibly complex, possessing multiple different compartments that communicate with each other, intricate microarchitecture within these compartments, and many different cell types within each compartment. Bioprinting involves recreating the 3D structure of a tissue using a fabrication technique where a computer program slices up a construct into discrete layers and rebuilds them using a biomaterial. These biomaterials are designed to mimic the architecture of the extracellular matrix in which cells are suspended. Additionally, cells themselves can be incorporated into these constructs. Accordingly, a complex organ may be built step-by-step using the 3D images, such as those from MRI and CT scans, native cells from a patient, and biologically compatible materials.
Thus, there is a need for devices, systems, and methods for bioprinting tissues and organs, without the need for donor organs in transplantation surgeries and animal testing in a number of industries. The invention is directed to these and other important needs.